But they kept going back to fix the map to make it more gerrymandered. That’s undisputed. The people involved in the process had traditional maps that complied with traditional criteria and then went back and threw out those maps and created more -- some that were more partisan. . . . So why didn’t they take one of the earlier maps?

JUSTICE SOTOMAYOR

Could you tell me what the value is to democracy from political gerrymandering? How -- how does that help our system of government?

Appellee’s Test

The appellees lay out their test for determining partisen gerrymandering:

First, it must find that the map was designed with discriminatory intent: “to place a severe
impediment on the effectiveness of the votes of individual citizens on the basis of their political
affiliation.” Second, it must determine that the map causes a “large and durable” discriminatory effect: one that is “sizeable” and likely to “persist throughout the decennial period.” And third, it must conclude that there is no valid justification for this effect: no way to explain it the legitimate state prerogatives and neutral factors that are implicated in the districting process.”

False Positives

The problem with false positives:

Ms. MURPHY

Sure. So I think some of the problems with the criteria that have been suggested, in particular with the tests that focus on these symmetry metrics, is that so far the metrics that we have, I mean, they identify false positives roughly 50 percent of the time.

Mr. TSEYTLIN

This is plain -- Plaintiff’s expert studied maps from 30 years, and he identified the 17 worst of the worst maps. What is so striking about that list of 17 is that 10 were neutral draws.